Collection: GC Septa & Accessories

On heavily used instruments, routine practice is to change the septum daily or at least on a fixed injection-count schedule — waiting for failure costs more in troubleshooting than the septum itself. Replace immediately if you see retention time shifts, baseline drift, or loss of response, which point to a leaking or cored septum. Hamilton's Long Life design stretches the interval by guiding the needle to a pre-pierced center point.

Heated septa slowly release volatile siloxane compounds that condense at the head of the column during cool-down and elute as ghost peaks or a rising baseline when the oven heats up. Septum fragments cored into the inlet liner cause the same symptoms. Preconditioned low-bleed septa, such as Hamilton's PTFE and silicone rubber septa, plus a continuous septum purge flow, remove most of the problem.

Match the septum to your inlet temperature: Hamilton High Temperature GC septa (preconditioned PTFE/silicone rubber, 3.175 mm thick) are rated to a maximum operating temperature of 212 °C, while Three Layer septa (preconditioned silicone rubber, 3.81 mm) are rated to 200 °C. Running a septum above its rating accelerates bleed and hardening.

Coring happens when the needle punches out a plug of septum material into the inlet. Use the right needle geometry — Hamilton reports its conical Point Style AS needles can extend septa life as much as 10-fold compared with beveled points — and consider Long Life septa, whose pre-pierced center depression guides every injection to the same point and reduces needle bending.

Hamilton GC septa are held in local stock by Danyel Biotech, the official Israeli distributor for Hamilton laboratory products — the same source as your syringes and needles, so the whole injection path arrives together. Quotes go out fast from this page.